Voters are going to the polls on primary day in triple digit heat, which threatens to break records across much of Kansas and Missouri.

(CNN) – When they say Tuesday is a barn burner in Kansas and Missouri, they're talking about more than close primary races.

Voters are going to the polls on primary day in triple digit heat, which threatens to break records across much of the region.

In Wichita, the National Weather Service said it was already 100 degrees at 11:30 a.m. CDT, with a record high of 108 expected and a heat index over 110.

But officials, who predicted an increase in turnout over previous midterm primaries, did not expect the stifling temperatures to keep many voters away.

"It could have some, but primary voters are a fairly dedicated group, so we don't expect a huge impact", Kansas Secretary of State spokeswoman Abbie Hodgson said, "We are quite used to 100 degree days."

Kansas officials were predicting 19 percent of eligible voters to cast ballots, higher than the 2006 primary but below the 2008 presidential primary turnout. Hodgson said early voting and mail-in ballots helped increase it despite the weather.

In Missouri, the Secretary of State's office forecast a 24 percent turnout topping the 17 percent for the last midterm primary.

Communications Director Laura Egerdal said "there are lots of things that drive turnout" regardless of the temperatures, "We've had interesting weather in recent years for elections – ice storms, tornadoes. But Missouri voters always seem to come to the polls".

Some of the heaviest turnout was expected in Missouri's Greene County, in the southwestern part of the state. County Clerk Richard Struckhoff said voting in eight bellwether precincts was up over the 2006 primary as of 11 a.m. CDT, but he was watching for a possible drop off as the heat increased later in the day.

"It will definitely discourage people from going if they're heat sensitive. All but one of our polling places are air conditioned, but getting there can be a burden.'

He said extra fans were brought into that polling station, an old school building, and doors were being kept open. One small office there had air conditioning, and was being used for poll workers who needed a break from the heat.

But Struckhoff said, "that's just Missouri in August".

In Wichita, the National Weather Service said it was already 100 degrees at 11:30 a.m. CT, with a record high of 108 expected and a heat index over 110.

But officials, who were predicted an increase in turnout over previous midterm primaries, did not expect the stifling temperatures to keep many voters away.

"It could have some, but primary voters are a fairly dedicated group, so we don't expect a huge impact", Kansas Secretary of State spokesperson Abbie Hodgson said, "We are quite used to 100 degree days."

Kansas officials were predicting 19 percent of eligible voters to cast ballots, higher than the 2006 primary but below the 2008 presidential primary turnout. Hodgson said early voting and mail-in ballots helped increase it despite the weather.

In Missouri, the Secretary of State's office forecast a 24 percent turnout topping the 17 percent for the last midterm primary.

Communications Director Laura Egerdal said "there are lots of things that drive turnout" regardless of the temperatures, "We've had interesting weather in recent years for elections – ice storms, tornadoes. But Missouri voters always seem to come to the polls".

Some of the heaviest turnout was expected in Missouri's Greene County, in the southwestern part of the state. County Clerk Richard Struckhoff said voting in eight bellwether precincts was up over the 2006 primary as of 11 a.m. CT, but he was watching for a possible drop off as the heat increased later in the day.

"It will definitely discourage people from going if they're heat sensitive. All but one of our polling places are air conditioned, but getting there can be a burden," Struckhoff said.

He said extra fans were brought into that polling station, an old school building, and doors were being kept open. One small office there had air conditioning, and was being used for poll workers who needed a break from the heat.